摘要
自六十年代起，由于电子显微镜的广泛应用，使硅藻的形态学及分类学的研究日益深入。近年来由于采用硅藻壳壁上二种超微结构——唇形突(Labiate process)和支持突(strutted process)的形态、数量及其在壳面上的分布在不同的科、属、种的表现不同作为分类标准，使得从十九世纪末以来所采用的形态学的分类依据有了重大的突破。
A new species, Thalassiosirs scrotiformis from the East China Sea is studied.It is a pocketlike colony, with diameter 0.1-1.3cm. Cells are convex lens shaped. Valve circular convex,33-44μm in diameter. Mentle oblique. Sculpturing very delicate, sometimes not visible in light microscope. Valves surface divided into sectors bounded by curved rays, the arealae are runig parallel to the middle ray of each sector. Arealae about 15-16 in 10pm,nearly same size on entire valve. Some intercalary bands are present. Foramina are external and cribra internal. The valve surface shows two kinds processes, one is labiate process, it is near margin, the other kind is strutted process, which has one central strutted process and a ring of margin strutted processes, besides, there are some one irregular scattered over valve.Thalassiosira subtilis and Thalassiosira mala are compared to closely ralated species.The type location for this species is Lat. 29°35.3'---30°30.'N,Long. 126°30.0'-127°32.1'E.Types (81-12-F1-141) are placed in the Department of Marine Biology, Shandong College of Oceanology.
